Milliwatt is 0.001 watt units.
Milliwatts to Kilowatts Converter — mW to kW
Convert Milliwatt (mW) to Kilowatt (kW) using the exact conversion factor (1 milliwatt = 0.000001 kilowatt). See the formula, worked examples, conversion table, history, and common uses.
Milliwatts to Kilowatts converter
Converter
Power Converter
Convert watts, horsepower, refrigeration tons, BTU per hour, and engineering power units.
Context values
Some unit families need one extra value for a physically accurate result.
Kilowatt is 1000 watt units.
Result = input x 0.001 / 1000.
Power uses the watt as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Milliwatts to Kilowatts
Milliwatt and Kilowatt both describe power output, and the conversion is a routine part of comparing an engine or motor's spec sheet across countries that use different power units. Specifically: Milliwatt is 0.001 watt units, and kilowatt is 1000 watt units.
Formula
kilowatts = milliwatts × 0.000001
This factor comes from each unit's defined relationship to the category's base unit: 1 milliwatt equals 0.001 base units, and 1 kilowatt equals 1000 base units, so dividing one by the other gives the direct milliwatt-to-kilowatt factor of 0.000001.
Simple example
1 mW × 0.000001 = 0.000001 kW
1 milliwatt = 0.000001 kilowatts.
Real-world example
100 mW × 0.000001 = 0.0001 kW
100 milliwatts = 0.0001 kilowatts.
Conversion table
| Milliwatt (mW) | Kilowatt (kW) |
|---|---|
| 1 mW | 0.000001 kW |
| 10 mW | 0.00001 kW |
| 100 mW | 0.0001 kW |
| 500 mW | 0.0005 kW |
| 1,000 mW | 0.001 kW |
| 5,000 mW | 0.005 kW |
Reverse conversion: Kilowatt to Milliwatt
0.000001 kW × 1000000 = 1 mW
0.000001 kilowatts = 1 milliwatt.
milliwatts = kilowatts × 1000000
For a page dedicated to this direction, see Kilowatt to Milliwatt.
Understanding the Milliwatt (mW)
Milliwatt is 0.001 watt units.
Understanding the Kilowatt
Kilowatt (kW) measures power. A kilowatt is 1,000 watts. It is classified as a SI derived (metric prefix) unit.
Where it's used: Standard power unit worldwide for larger appliances, vehicles, and electrical systems
Uses of the Kilowatt today
- Electric vehicle motor power ratings (alongside horsepower)
- Household electrical system and generator capacity
- Industrial motor and equipment power ratings
History of the Kilowatt
The kilowatt follows directly from the watt via the standard SI 'kilo-' prefix, becoming especially prominent with the growth of electrical power generation and distribution in the late 19th and 20th centuries.
Historical origin. Kilowatt was not the invention of a single named person; it developed through the process described above.
Kilowatt — sources
- BIPM SI Brochure — SI prefixes — Defines 'kilo-' as the prefix for 10³.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many kilowatts are in 1 milliwatt?
1 milliwatt equals 0.000001 kilowatts, using the exact defined conversion factor rather than an estimate.
How do I convert milliwatt to kilowatt?
Multiply the milliwatt value by 0.000001. The converter above does this instantly to whatever precision you set.
How do I convert kilowatt back to milliwatt?
Use the reverse factor: 1 kilowatt equals 1,000,000 milliwatts. You can also use the swap control in the converter above to flip the direction instantly.
What is a milliwatt?
Milliwatt (mW) is a unit of power.
What is a kilowatt?
Kilowatt (kW) measures power. A kilowatt is 1,000 watts. It is classified as a SI derived (metric prefix) unit.
Is the milliwatt to kilowatt conversion exact?
Yes. Both milliwatt and kilowatt are defined by fixed standards rather than physical artifacts, so the factor of 0.000001 used above is exact to as many digits as you choose to display.